dynamic modeling of the chariot suspension system joseph shoer / es6 exit presentation 7 august 2009
TRANSCRIPT
Dynamic Modeling of the Chariot Suspension System
Joseph Shoer / ES6Exit Presentation
7 August 2009
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureIntroductionIntroduction
Personal Background
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Magnetic Flux PinningAutonomous dockingModular self-assemblyLarge-scale structuresSystem reconfiguration
IntroductionIntroduction
www.SpacecraftResearch.com
Space Systems Research at Cornell
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureIntroductionIntroduction
Chariot Small Pressurized Rover (SPR)
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureIntroductionIntroduction
Chariot Small Pressurized Rover (SPR)
Planetary surface exploration requires mobility
SPR allows extended (days-weeks) traverses with high visibility and relatively easy ingress/egress
Traverse rugged planetary terrains to high science value targets
ES supports ER in Gen 1 concept analysis and Gen 2 vehicle development
Chariot Rover Development
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureIntroductionIntroduction
Chariot Small Pressurized Rover (SPR)
Stress, loads and design support prior to Gen 2
Support Gen 1 Rover failure analyses
Support Gen 2 design recommendations
Develop FEM component models
Cabin pressure vessel
Develop rigid body model
ES Rover Involvement
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureIntroductionIntroduction
Chariot Small Pressurized Rover (SPR)
Stress, loads and design support prior to Gen 2
Support Gen 1 Rover failure analyses
Support Gen 2 design recommendations
Develop FEM component models
Cabin pressure vessel
Develop rigid body model
ES Rover Involvement
Focus on Suspension System
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureIntroductionIntroduction
Develop a dynamic model of the vehicle
suspension to help understand dynamic
loads on the suspension system in the
operating environment.
This will promote optimal vehicle design
in Gen 2 development.
Objective
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureADAMS ModelADAMS Model
ADAMS Model Components
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
210 kg each
Wheel modules
ADAMS ModelADAMS Model
ADAMS Model Components
960 kg
Cabin
210 kg
Frame
1200 kg total
Nonstructural masses
740 kg
Balance
24 cm forward
CG
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureADAMS ModelADAMS Model
Suspension System Dynamic Model
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureADAMS ModelADAMS Model
Suspension System Dynamic Model
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Joints with 5DOF stiffness
ADAMS ModelADAMS Model
Four-bar linkages
Suspension System Dynamic Model
Spring
Ground
Vehicle weight
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureADAMS ModelADAMS Model
Suspension System Dynamic Model
Key component for loads Previous failure analysis FEM in development
(Photo: Leslie Schaschl/ES4)
Key component for loads Previous failure analysis FEM in development
(Photo: Leslie Schaschl/ES4)
Back Plate
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Stiffness: 600 lbf/in Damping from data
ADAMS ModelADAMS Model
Passive spring/dampers
Suspension System Dynamic Model
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureADAMS ModelADAMS Model
Ball ScrewMotor
Suspension System Dynamic Model
Moves along ball screw(Change spring endpoint) Actuates suspension angle
Screw Rail
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Wheel module / frame
Tire stiffness from data Simple tire damping Tire/ground friction
Constant speed rotation
Tire-ground contact
ADAMS ModelADAMS Model
Fixed joint
Suspension System Dynamic Model
Wheel drive motion
Crab angle
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Simulation Capabilities: Dynamic BehaviorsCapabilitiesCapabilities
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Simulation Capabilities: Dynamic BehaviorsCapabilitiesCapabilities
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Simulation Capabilities: Result Sets
Extract Forces in Joints or Bodies
Extract Torques in Joints or Bodies
CapabilitiesCapabilities
ADAMS can also extract stresses in flex bodies
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe FutureCapabilitiesCapabilities
Simulation Capabilities: Active Suspension
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Improve nonstructural mass distribution Improve tire/ground interaction model
(“Sinking” issue, ground and tire materials) Improve active control implementation
(Sensor, motor dynamics; control law)
The FutureThe Future
Model Fidelity Improvements
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Implement additional control modes
(steering assist, climbing, etc) Include FEM flexible bodies
(back plate, bushings, etc) Add runtime wheel steering
(run test courses)
The FutureThe Future
Model Extension Possibilities
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Add wireless instrumentation to vehicle Characterize suspension accelerations Input to model
The FutureThe Future
Experimental Correlation
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Conclusions
ES6 now has a multibody dynamics model for the six-wheeled SPR
This model promises excellent possibilities for improvement and extension
This model can provide stress and load information under dynamic conditions, which will feed into optimization and development for the Gen 2 rover
IntroductionIntroduction ADAMS ModelADAMS Model CapabilitiesCapabilities The FutureThe Future
Alex TovarTim Rupp
John SchliesingEd Herrera
Beverly HaygoodCourtney Crooks
Some images from EA Imagery Online library
Acknowledgments
Dynamic Modeling of the Chariot Suspension System
Joseph Shoer / ES6Exit Presentation
7 August 2009